What is the molarity of a solution in which 0.23 moles of NaCl are dissolved in enough water to make 395.6 mL of solution

Answer:

no it is not a complete model

Hello there!

Answer:

A. <

Explanation:

You should remember that all negative numbers are smaller then positive numbers. For example, -10 < 7 or -9479 < 1

-4 is a negative integer

0.598 is a positive number

So -4 < 0.598 (negative < positive)

The vinegar also caused the egg white to become more acidic, making it easier to separate from the yolk. Additionally, the vinegar helped preserve the egg by preventing bacteria from growing on the eggshell.

Bacteria are microscopic organisms that exist virtually everywhere in nature. They range in size from 0.2 to 0.8 micrometers and can be found in soil, water, air, and even inside other organisms. Bacteria can reproduce rapidly, and some species can form biofilms that make them resistant to antibiotics. Bacteria can have beneficial roles in food production, soil fertility, and human and animal health. They can also cause diseases, such as cholera, meningitis, and tuberculosis. Bacteria are able to adapt quickly to changing environments and can become resistant to antibiotics.

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Answer:

GOT YOU

Explanation:

Jotun (pollinator)

Norse(decomposer)

Its a point and click adventure game. Where you only have specific actions you can do with your mouse. The basic options are Inspect for notes or Pollinate pollinate the right plants to escape. Your goal and how to win is go through each level picking up the plants to pollinate leave the level. The only way to lose is if you are unable to find the right plants by a set amount of time. The story is your wife has been taken prisoner by Norse and you are alerted by this from a note. You go to a location and find a tower once you walk in the doors shut behind you and a screen appears saying "Get out of the room and to the top of the tower in an hour or she dies. Jotun escapes and gets to the top of the tower to find out his wife died long ago and Norse has been using her for food.

Inside the metric system, length as well as distance were two of the most significant metrics. Measurement of length and distance can be done in a variety of ways.

Using a metre stick is among the most popular methods for gauging these amounts.

A meterstick, meterstick, nor yardstick consists of either a straightedge as well as foldable ruler was using to measure length, and therefore is notably common inside the construction business. They frequently consist of wood as well as plastic, and their joints frequently consist of plastic as well as metal to allow for folding.

A metre stick is a highly helpful tool in science that is exactly one metre long. A metre stick can be used to gauge items and distances that are both less than as well as longer than one metre.

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Answer:

C. 7370 joules.

Explanation:

There is a mistake in the statement. Correct form is described below:

Using the above data table and graph, calculate the total energy in Joules required to raise the temperature of 15 grams of ice at -5.00 °C to water at 35 °C.

The total energy needed to raise the temperature is the combination of latent and sensible heats, all measured in joules, and represented by the following model:

[tex]Q = m\cdot [c_{i} \cdot (T_{2}-T_{1})+L_{f} + c_{w}\cdot (T_{3}-T_{2})][/tex] (1)

Where:

[tex]m[/tex] - Mass of the sample, in grams.

[tex]c_{i}[/tex] - Specific heat of ice, in joules per gram-degree Celsius.

[tex]c_{w}[/tex] - Specific heat of water, in joules per gram-degree Celsius.

[tex]L_{f}[/tex] - Latent heat of fusion, in joules per gram.

[tex]T_{1}[/tex] - Initial temperature of the sample, in degrees Celsius.

[tex]T_{2}[/tex] - Melting point of water, in degrees Celsius.

[tex]T_{3}[/tex] - Final temperature of water, in degrees Celsius.

[tex]Q[/tex] - Total energy, in joules.

If we know that [tex]m = 15\,g[/tex], [tex]c_{i} = 2.06\,\frac{J}{g\cdot ^{\circ}C}[/tex], [tex]c_{w} = 4.184\,\frac{J}{g\cdot ^{\circ}C}[/tex], [tex]L_{f} = 334.72\,\frac{J}{g}[/tex], [tex]T_{1} = -5\,^{\circ}C[/tex], [tex]T_{2} = 0\,^{\circ}C[/tex] and [tex]T_{3} = 35\,^{\circ}C[/tex], then the final energy to raise the temperature of the sample is:

[tex]Q = (15\,g)\cdot \left[\left(2.06\,\frac{J}{g\cdot ^{\circ}C} \right)\cdot (5\,^{\circ}C)+ 334.72\,\frac{J}{g} + \left(4.184\,\frac{J}{g\cdot ^{\circ}C}\right)\cdot (35\,^{\circ}C) \right][/tex]

[tex]Q = 7371.9\,J[/tex]

Hence, the correct answer is C.

Answer:

A solar eclipse .

It is one that occurs when the moon gets between the Earth and the Sun and it casts its shadow over the Earth. A solar eclipse only happens during the phase of new moon when the moon is indirect blockage of sun rays from reaching the earth thus causing a full shadow of the moon to fall on the Earth’s surface.

2 A lunar eclipse can only occur when there is a full moon. An eclipse of the moon happens only at full moon and only when the moon passes through some portion of the Earth’s shadow. The shadow in made of a two cone-shaped components, one which is nested inside the other.

3.  Earth blocks sunlight from reaching the moon's surface. There are three categories of lunar eclipse according to the blockage of the sun rays. In a penumbral lunar eclipse, the moon passes through Earth’s penumbral shadow. The partial lunar eclipse occurs when a portion of the moon passes through Earth’s umbral shadow. The total lunar eclipse happens when the entire moon passes through Earth’s umbral shadow.

4.When an object in space comes between the sun and earth. It is one that occurs when the moon gets between the Earth and the Sun and it casts its shadow over the Earth. A solar eclipse only happens during the phase of new moon when the moon is indirect blockage of sun rays from reaching the earth thus causing a full shadow of the moon to fall on the Earth’s surface.

5.A total lunar eclipse. In this type of lunar eclipse, the events are clearly visible and striking to view because the Moon surface appear red in color. During the occurrence of the lunar eclipse events, 35% of the entire eclipse is total eclipse.

6. Wide, dark areas and strange spots and ridges –Galileo described the surface of the moon as being uneven and rough. In addition to that, he described the surface as crowded with depressions and bulges. In his original sketches, the long shadows cast by craters were represented by dark sided of the moon sketch.

7. Waxing gibbous .During the cycle of the moon, it undergoes several phases; new moon-new crescent-first quarter-waxing gibbous-full moon-waning gibbous-last quarter-old crescent-new moon. The new moon phase cannot be seen because the part receiving sun rays in then pointed away from the earth. The rest of the phases are visible from the earth.

8. New moon .

During the cycle of the moon, it undergoes several phases; new moon-new crescent-first quarter-waxing gibbous-full moon-waning gibbous-last quarter-old crescent-new moon. The new moon phase cannot be seen because the part receiving sun rays in then pointed away from the earth. The rest of the phases are visible from the earth.

9. Because the Southern Hemisphere has more direct sunlight .During the winter months, the Northern Hemisphere is tilted away from the sun, thus it receive sunrays at an angle thus it experiences the cold weather. At this period, it is summer in the Southern Hemisphere.

Explanation:

The moon is the earth's closed satellite and it gets light from the sun. The moon has several phases that are seen within 27 days cycle.

Hence as the earth changes its position the moon also revolves in a similar manner.

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Answer:

U could use the formula

Explanation:

To calculate the number of atoms in a sample, divide its weight in grams by the amu atomic mass from the periodic table, then multiply the result by Avogadro's number: 6.02 x 10^23

Ferric oxide, is the product that is formed when iron undergoes oxidation

Upon reacting with oxygen, iron will be oxidized to either the +3 oxidation state in iron (III) oxide, or to a combination of the +2 and +3 oxidation states in iron (II, III) oxide.The balanced chemical equations for these reactions look like this

#4”Fe”_text((s]) + 3”O”_text(2(g]) -> 2”Fe”””_2”O”_text(3(s])#

And

#3”Fe”_text((s]) + 2”O”_text(2(g]) -> “Fe”””_3”O”_text(4(s])#

The first compound, iron (III) oxide, also called ferric oxide, is dark red/brown in color

While the second compound, iron (II, III) oxide, also called ferrous ferric oxide, is dark brown/black in color.The [Fe(H2O)6]3+ ion is colorless (or pale pink), but many solutions containing this ion are yellow or amber-colored because of hydrolysis.

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Answer:

Explanation:

Would you expect metals to have high ionization energies or low ionization energies? Support your answer by relating ionization energy to the formulation of ions.

By natural process, elements individually gain or lose electrons by the path of least resistance to form an element with a Noble Gas electron configuration. That is, elements containing less than 4 electrons (Groups IA through Groups IIIA and include the Transition Elements) tend to lose electrons and become positive cations. Elements containing 4 or more valence electrons generally tend to gain electrons forming negative anions. In general, the elements forming cations are collectively ‘The Metal Elements’ and the elements forming anions are collectively ‘The Nonmetal Elements’.  

The chart following the explanation text shows metals in blue, metalloids in green and nonmetals in yellow. In general, metals tend to lose electrons, nonmetals tend to gain electrons and metalloids sometimes gain and sometimes lose depending upon the compound of interest.  

(see chart at end of explanation)*

Trends in ionization energy depend upon three factors, 1. Atomic and Ionic Radii, 2. The amount of energy needed (gain/endothermic process) to remove electrons from the element’s electronic structure and 3. ‘Electron Affinity’ an energy term describing the amount of energy lost (exothermic process) when an electron is added into the valence shell of an element.  

Atomic and Ionic radii of metals tend to decrease with increasing atomic number. That is, in a given series the 1st element would have the largest atomic and ionic radii and sequentially decrease through the smaller radii as atomic number increases. In order of increasing atomic number the following 1st ionization energies (removal of 1st electron) are known for the listed metallic elements of series 2 of the periodic table:

Li + 520Kj/mole => Li⁺ + eˉ (valence electron is farther away from nucleus than the next two elements in series.)

Be + 900Kj/mole => Be⁺ + eˉ  (electronic orbital structure is more stable for the 1st 2eˉs)

B + 801Kj/mole => B⁺ + eˉ (electron orbital structure is less stable (easier to remove) for 3rd electron requiring a lower ΔEᵢ.)

In the series, the elements are increasing in proton and electron number resulting in smaller radii and stronger attractive electrostatic forces (stronger bond) between the nucleus and electron cloud. Relating this trend to the 1st ionization energy values shown above, the larger radii requires lower ionization energies as the valence electron is farther from the nucleus with a weaker bond than subsequent elements in the same series.  

In a more fundamental context, consider Lithium (Li) with its 1 valence electron. By path of least resistance concept (see 1st sentence), would it be more reasonable for lithium to gain 7 electrons to achieve a Noble Gas configuration (i.e., Ne) or lose 1 electron to achieve the Noble Gas configuration (i.e., He)? By natural path of least resistance, Li would tend to lose its one valence electron forming the cation Li⁺. Of course, with a little thought, gaining 7 electrons would be improbable as lithium has only 3 protons (+); certainly not enough attractive force to hold 8 electrons (1e⁻ + 7e⁻ gained).

Solid silicon and solid magnesium chloride form when silicon tetrachloride gas reacts with magnesium metal. the equation is :

SiCl₄(g)  +  Mg(s)   --->  Si(s)  +  MgCl₂(s)

When the solid silicon react with the solid magnesium chloride , the word equation is :SiCl₄(g)  +  Mg(s)  

the product formed is the silicon tetrachloride gas. the word equation is :

Si(s)  +  MgCl₂(s)

The unbalanced equation is :

SiCl₄(g)  +  Mg(s)   --->  Si(s)  +  MgCl₂(s)

The balanced equation for the reaction of the silicon tetra chloride react with the magnesium   and form the silicon  and the solid magnesium chloride.  and t is given :

SiCl₄(g)  +  Mg(s)   --->  Si(s)  +  MgCl₂(s)

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The mole fraction of ethanol, C2H5OH is 0.076 that can be calculated by using the density of water.

The mole fraction of any solution is described because the ratio of the quantity of moles of that is present withinside the technique to the entire quantity of moles of all of the additives of the solution. Molarity on the other hand is the ratio of moles to the volume.

Molecular mass of ethanol = 46g

The molarity of the solution is 4.6 molal=4 moles in 1L solution

Molecular mass of water =18g

Density of water = 1kg/m3 = 1000g/L

So, mass of water in 1 l solution = 1000g

So moles = 1000/18 = 55.55 moles

Thus, mole fraction of ethanol= 4.6/(4.6+55.6) =0.076

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The six physical properties associated with hazard recognition of hazardous materials/chemicals are Flammability, Reactivity, Toxicity, Corrosivity, Physical hazards, Health hazards are explained below with details.

1. Flammability: The ability of a material to catch fire and burn easily.

2. Reactivity: The ability of a material to chemically react with other materials, including the potential for explosions or release of toxic gases.

3. Toxicity: The ability of a material to cause harm or death when ingested, inhaled, or absorbed through the skin.

4. Corrosivity: The ability of a material to eat away at or damage other materials, including metals and human tissue.

5. Physical hazards: The potential of a material to cause harm through physical means, such as pressure, impact, or friction.

6. Health hazards: The potential of a material to cause harm to human health, including acute and chronic effects.

These are the six physical properties associated with hazard recognition of hazardous material.

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Answer: Filterability Test

Explanation: This involves filtering the liquid through a filter paper to see if the particles pass through or are retained on the paper. If the particles pass through, the liquid is likely a solution. If the particles are retained, the liquid is likely a colloid. The technical name for this test is the separation test.

Answer:

One way to determine whether a transparent liquid is a solution or a colloid is to use the Tyndall effect. The Tyndall effect, also known as the Tyndall scattering, is a phenomenon that occurs when a beam of light passes through a colloidal system (a mixture in which one substance is dispersed evenly throughout another). When this happens, the light is scattered by the particles in the colloidal mixture, causing the mixture to appear hazy or cloudy. In contrast, if the transparent liquid is a true solution (one in which the solute is completely dissolved in the solvent), the light will pass through it without being scattered, and the solution will appear clear.

To perform the Tyndall effect test, you would need a light source (such as a flashlight or a laser pointer) and a dark room or area. Place the transparent liquid in a clear container, and shine the light through it. If the light is scattered by the particles in the mixture, it will be visible as a bright beam or spot on the opposite side of the container. If the light passes through the mixture without being scattered, it will appear as a continuous, unbroken beam.

There are other tests that can be used to distinguish between solutions and colloids, such as the filterability test and the centrifugation test. However, the Tyndall effect test is one of the most straightforward and reliable methods for making this distinction.

Explanation:

The rate constant of the reaction is 0.56 M⁻¹s⁻¹. The time required to change the concentration of the reactant from 0.900 to 0.100 M is 15.87s.

The half-life of a reaction can be defined as the time needed for a reactant to reach one-half of its initial concentration. For a 1st-order reaction, the half-life is independent of concentration and constant with time.

The half-life period of the second-order reaction can be written as:

[tex]\displaystyle t_{1/2} =\frac{1}{k[A]_o}[/tex]

Given the half-life of the reaction = 2.00 s

The initial concentration of [NOBr]₀ = 0.900 M

The rate constant of the reaction, k = 1/2 ×0.900 = 0.56 M⁻¹s⁻¹

The time required to change concentration from 0.900 to 0.100 M is:

[tex]\displaystyle kt =\frac{1}{[A]} -\frac{1}{[A]_o}[/tex]

0.56 ×t = 1/0.1 -1/0.9

t = 15.87 s

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Glycolysis during fermentation only yields two ATP each glucose molecule, which is significantly less ATP than is produced during respiration.

A collection of more than two atoms joined by chemical bonds is referred to as a molecule. The compound is a mixture made up of two or more distinct kinds of elements that are chemically combined in a predetermined ratio. Not every molecule is a compound. Molecules make up all chemicals.

According to the context, it term might or might not include ions that meet this requirement. A molecule is a collection of atoms that are held together by the attractive forces called as chemical bonds.

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Answer:

6 min 40 sec

Explanation:

Hope this helps you :)

The difference between the arrival time of the first P-wave and the arrival time of the first S-wave recorded at the station will be 6 minutes 40 seconds.

P waves move the fastest and arrive first from the earthquake. Rock oscillates perpendicular to the direction of wave propagation in S or shear waves.

In rock, S waves move at approximately 60% the speed of P waves, and the S wave always comes after the P wave. Sound waves, for example, are P waves with a high enough frequency to be heard with your ear.

Wiggling or shaking a rope that is tied down at one or both ends is an example of a S wave.

Both P and S waves propagate outward from an earthquake focal point within the ground.

The waves are frequently observed as independent arrivals on seismographs located at great distances from the earthquake. The direct P wave arrives first because its course takes it through faster moving, denser rocks deeper in the ground.

Because they pass through deeper, lower velocity rocks, the PP (one bounce) and PPP (two bounces) waves move more slowly than the straight P. After the P waves, the various S waves arrive.

To conclude with we can say that Seismic waves or body waves are elastic waves created when the earth's crust is disturbed. The wave is classified into two types  body waves and surface waves. The P and S - waves that move through the ground are body waves.

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Answer:

[tex]p_O=818.2torr[/tex]

Explanation:

Hello there!

In this case, according to the given equation, it is possible to calculate the mass of oxygen by using the Dalton's law, considering that the total pressure is 850 torr and the vapor pressure of water at 30°C is 31.8 torr:

[tex]P_T=p_O+p_{H_2O}[/tex]

Thus, we solve for the pressure of oxygen as follows:

[tex]p_O=P_T-p_{H_2O}\\\\p_O=850torr-31.8torr\\\\p_O=818.2torr[/tex]

Best regards!

A substance has 0. 0152088 moles per 10 grammes. One can use the equation grams = weight / molar mass to determine this. The volume of one mole of a chemical is represented by its molar mass on the chemical elements.

You would take its weight (10g) and multiply it by the material's molar mass to determine the number of molecules within 10g of a substance. For instance, if the material is water, its molar mass is 18. 015 g/mol, meaning that 10 g is comparable to 0. 555 molecules of water.

However, the formula moles = mass / molar weight can be used to determine the number of moles in an unit weight regardless of the substance. Therefore, there are 0. 0152088 mole in 10

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The element with 14 protons 14 neutrons and 14 electrons is Silicon

Protons and neutrons can both be found in the nucleus of an atom of any chemical element. These subatomic particles add up to give the atom's atomic mass. The characteristic that distinguishes isotopes of different elements from one another is their atomic mass.

Z, the atomic number, is 14 if there are 14 protons. Z being the quantity of large positively charged nuclear particles by definition. And Z establishes the atom's identity; if Z = 14,we can find on periodic table element that have atomic number 14 is silicon,

Therefore element with 14 protons 14 neutrons and 14 electrons is Silicon

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We need to take 5ul of stock solution and add it to 5ul of diluent to achieve a final concentration of 100ug/L.

To solve this problem, you will need to create a stock solution of the chemical substance and then dilute it to the desired concentrations. Here's one way you could approach it:

Create a stock solution by dissolving the 5mg of powder in a solvent with a 2g/L solubility. We know that the solubility of the substance is 2g/L, so we can use the formula:

Stock solution concentration = (mass of substance) / (volume of solvent)

In this case, the mass of the substance is 5mg and the volume of solvent is 1L. So, the stock solution concentration is:

5mg / (1L) = 5mg/L

Dilute the stock solution to the desired concentration for the first dose of 10ug/L. To do this, we can use the formula:

Desired concentration = (volume of stock solution) / (volume of diluent)

In this case, we want a final concentration of 10ug/L, so we'll let the volume of stock solution be x and the volume of diluent be (5ul-x). Then we can set up the equation:

10ug/L = (x) / (5ul-x)

Solving this equation:

x = 0.5ul

Therefore, we need to take 0.5ul of stock solution and add it to 5ul of diluent to achieve a final concentration of 10ug/L

Dilute the stock solution to the desired concentration for the second dose of 100ug/L. Using the same formula as before:

Desired concentration = (volume of stock solution) / (volume of diluent)

In this case, we want a final concentration of 100ug/L, so we'll let the volume of stock solution be y and the volume of diluent be (10ul-y). Then we can set up the equation:

100ug/L = (y) / (10ul-y)

Solving this equation:

y = 5ul

Therefore, we need to take 5ul of stock solution and add it to 5ul of diluent to achieve a final concentration of 100ug/L

So, you can create a stock solution by dissolving 5mg of powder in a solvent with 2g/L solubility and obtain a stock solution of 5mg/L. With this stock solution, you can create two dilutions, the first one is 10ug/L by adding 0.5ul of stock solution to 5ul of diluent, and the second one is 100ug/L by adding 5ul of stock solution to 5ul of diluent.

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Answer:

225 mL of water must be added.

Explanation:

First we calculate how many HCl moles are there in 516 mL of a 0.191 M solution:

Now we use that number of moles (that remain constant during the dilution process) to calculate the final volume of the 0.133 M solution:

We can calculate the volume of water required from the volume difference:

Answer:

A precipitate is formed as a result of a double displacement reaction. Explanation: When two substances (can be aqueous or liquids) in solution ...

In literary classes, the three most popular types are verbal irony, dramatic irony, and situational irony. When a speaker or narrator says something that contradicts what they mean, what they intend, or what the context necessitates, this is called verbal irony.

One thing is expressed while another is meant in an ironic statement. For example, on a chilly, wet gray day, you would exclaim, "What a gorgeous day!" Alternatively, if you were suffering from a severe case of food sickness, you may respond, "Wow, I feel terrific today." "ffers points of view and ideas that are, at most, intriguing... However, it does not reach the truth." Ronagh and Souder are particularly concerned with scientific assertions that are not meant to be taken seriously.

Here,

The three most common varieties in literary studies are verbal irony, dramatic irony, and situational irony. Verbal irony occurs when a speaker or narrator says something that contradicts what they mean, what they intend, or what the context requires.

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Answer:

4g of hydrogen

Explanation:

4g of hydrogen (molar mass 2) corresponds to 2 moles of molecules or 4N number of atoms where N is the Avogadro's number (6.023×10

23)

0.384 moles of nitrogen atoms are inhales by the person in an average breath of air.

Avogadro constant is the number of molecules present in 1 mole of gas or a chemical compound. It is used to specify the atomic mass of a certain number of molecules in a substance or chemical compound or gas, in grams. Theses molecules may be atoms, neutron, proton, electron, etc. One mole of a substance contains 6.023 × 10²³ Molecules. In other words the atomic mass of a substance is the weight of 6.023 × 10²³ molecules.

So 2.31 × 10²³ atoms of nitrogen = (2.31 × 10²³)/(6.023 × 10²³)

= 0.384 moles

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Answer:

did you mean to add or attach a paper to this? We need more info to help

Explanation:

Answer:Mars, earth, Uranus and Jupiter

Explanation:

The  E0cell for the halfcell that we have in the question is 3.73 V.

We have to know that the cell potential as we know it has to do with the electrical potential that is involved when we have the oxidation or the reduction of a given specie. In the case of what we have here, we have the cells that are composed of magnesium and chlorine and we want to find the electrode potential of the cells.

We must note that the basis that we can be able to use to find the electrode potential of the cell is the standard hydrogen electrode which has been assigned the value of about 0.00 V and all of the other cell potentials that we have can now be measured against this standard that has been fixed.

We have;

Magnesium half cell= -2.37 V

Chlorine half cell = + 1.36 V

Then we have;

E0cell = + 1.36 - (-2.37)

= 3.73 V

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The remaining mass of hydrogen that is present in the reaction is 0.20 grams.

The balanced chemical reaction can be depicted as follows:

2H2+O2---->2H2O

1 mole of Oxygen reacts with 2 moles of Hydrogen in order to produce two moles of water i.e., H2O.

0.15 moles of O2  reacts with 2 * 0.15 = 0.30 moles of H2

The moles of H2 are given i.e., 0.40 moles.

So remaining = 0.40 moles - 0.30 moles = 0.10 moles

Thus, the mass of H2 can be calculated by multiplying the number of moles with the molar mass that is expressed as follows:

Mass = moles * molar mass

Molar mass of H2= 2 g/mol

Mass of H2 remained in the reaction = 0.10 moles * 2 g/mole = 0.20 grams.

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